ABSTRACT A simple and efficient protocol for the synthesis of diaryl thioethers from the reaction of thiourea with a wide variety of aryl halides, including aryl iodides, aryl bromides and aryl chlorides in the presence of 3D hierarchical core-shell Fe3O4@NiO/Co3O4 microspheres has been described. This reaction enables the one-pot synthesis of diaryl thioethers in good to high yields using a non-toxic and magnetically separable catalyst in PEG-400 as an eco-friendly, safe, inexpensive and thermally stable solvent. Magnetic separation and reusability of catalyst for eight times without any significant loss of activity, the use of a commercially available, eco-friendly, cheap and chemically stable sulfur transfer agent and solvent, operational simplicity, environmentally benign, easier work-up procedure and cost efficiency make this method a promising candidate for potential applications in some organic reactions. The catalytic activity of Fe3O4@NiO/Co3O4 as a novel and inexpensive catalyst was investigated in the C-S cross coupling reaction. GRAPHICAL ABSTRACT

中文翻译：

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磁性可恢复铁磁性 3D 分层核壳 Fe3O4@NiO/Co3O4 微球作为聚乙二醇中 C-S 键形成的高效无配体催化剂

摘要 在 3D 分级核壳 Fe3O4@NiO/Co3O4 微球存在下，通过硫脲与多种芳基卤化物（包括芳基碘化物、芳基溴化物和芳基氯化物）反应合成二芳基硫醚的简单有效方案具有被描述。该反应能够在 PEG-400 中使用无毒且可磁分离的催化剂作为一种环保、安全、廉价且热稳定的溶剂，以良好至高产率的一锅法合成二芳基硫醚。磁分离和催化剂可重复使用八次而没有任何显着的活性损失，使用市售、环保、廉价且化学稳定的硫转移剂和溶剂，操作简单，对环境无害，更简单的后处理程序和成本效益使该方法成为某些有机反应中潜在应用的有希望的候选者。在 CS 交叉偶联反应中研究了 Fe3O4@NiO/Co3O4 作为一种新型廉价催化剂的催化活性。图形概要